The 26-year-old was badly burned in a fire that started some time after her car ran off the road and into bushland near Bonny Hills in the early hours of Saturday, August 16, 2003.

Less than five weeks later, Harmony died from her injuries while receiving treatment at Royal North Shore Hospital.

Now, six months on, Port Macquarie detectives are calling on the community to help them piece together the tragic puzzle.

The Bryant family is also desperate for answers, and is appealing to the public to help.

Harmony was last seen alive while visiting a friend at a Port Macquarie pharmacy about 5pm on August 15.

Less than 13 hours later - at 6am on Saturday, August 16, 2003 - police were called to a car fire in bushland off Ocean Dve, just south of Bonny Hills.

Harmony had received severe burns to 60 per cent of her body, and was flown from the scene to Newcastle's John Hunter Hospital.

She was later airlifted to Royal North Shore Hospital for treatment.

Constable Vanessa Partridge wants to speak to anyone who may know about Harmony's movements on the night of Friday, August 15, last year.

"We don't know where she was that night, who she was with or what she was doing.

"It has been suggested that Harmony was heading to Dunbogan to see a friend early that morning, but we don't know who that person is," Const Partridge said.

Harmony died on September 19, 2003, after spending five weeks in a critical condition - her family at her bedside.

Const Partridge said Harmony had returned to live in Port Macquarie with her family six weeks before the accident.

Detectives are investigating the death and will provide a report to the coroner.